[PATCH v3 06/12] drm/amdgpu: create kernel doorbell pages
Shashank Sharma
shashank.sharma at amd.com
Wed Jun 21 09:24:49 UTC 2023
On 21/06/2023 11:13, Christian König wrote:
>
>
> Am 21.06.23 um 11:10 schrieb Shashank Sharma:
>> Hey Christian,
>>
>> On 21/06/2023 10:32, Christian König wrote:
>>> Am 20.06.23 um 19:16 schrieb Shashank Sharma:
>>>> This patch:
>>>> - creates a doorbell page for graphics driver usages.
>>>> - adds a few new varlables in adev->doorbell structure to
>>>> keep track of kernel's doorbell-bo.
>>>> - removes the adev->doorbell.ptr variable, replaces it with
>>>> kernel-doorbell-bo's cpu address.
>>>>
>>>> V2: - Create doorbell BO directly, no wrappe functions (Alex)
>>>> - no additional doorbell structure (Alex, Christian)
>>>> - Use doorbell_cpu_ptr, remove ioremap (Christian, Alex)
>>>> - Allocate one extra page of doorbells for MES (Alex)
>>>>
>>>> Cc: Alex Deucher <alexander.deucher at amd.com>
>>>> Cc: Christian Koenig <christian.koenig at amd.com>
>>>> Signed-off-by: Shashank Sharma <shashank.sharma at amd.com>
>>>> ---
>>>> drivers/gpu/drm/amd/amdgpu/amdgpu_doorbell.h | 8 ++-
>>>> .../gpu/drm/amd/amdgpu/amdgpu_doorbell_mgr.c | 56
>>>> ++++++++++++++-----
>>>> drivers/gpu/drm/amd/amdgpu/amdgpu_mes.h | 3 +
>>>> drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c | 7 +++
>>>> 4 files changed, 60 insertions(+), 14 deletions(-)
>>>>
>>>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_doorbell.h
>>>> b/drivers/gpu/drm/amd/amdgpu/amdgpu_doorbell.h
>>>> index 783e2b8b086c..002899edb9d7 100644
>>>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_doorbell.h
>>>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_doorbell.h
>>>> @@ -31,10 +31,15 @@ struct amdgpu_doorbell {
>>>> /* doorbell mmio */
>>>> resource_size_t base;
>>>> resource_size_t size;
>>>> - u32 __iomem *ptr;
>>>> /* Number of doorbells reserved for amdgpu kernel driver */
>>>> u32 num_kernel_doorbells;
>>>> +
>>>> + /* Kernel doorbells */
>>>> + struct amdgpu_bo *kernel_doorbells;
>>>> +
>>>> + /* For CPU access of doorbells */
>>>> + uint32_t *cpu_addr;
>>>> };
>>>> /* Reserved doorbells for amdgpu (including multimedia).
>>>> @@ -311,6 +316,7 @@ void amdgpu_mm_wdoorbell64(struct amdgpu_device
>>>> *adev, u32 index, u64 v);
>>>> */
>>>> int amdgpu_doorbell_init(struct amdgpu_device *adev);
>>>> void amdgpu_doorbell_fini(struct amdgpu_device *adev);
>>>> +int amdgpu_doorbell_create_kernel_doorbells(struct amdgpu_device
>>>> *adev);
>>>> #define RDOORBELL32(index) amdgpu_mm_rdoorbell(adev, (index))
>>>> #define WDOORBELL32(index, v) amdgpu_mm_wdoorbell(adev, (index),
>>>> (v))
>>>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_doorbell_mgr.c
>>>> b/drivers/gpu/drm/amd/amdgpu/amdgpu_doorbell_mgr.c
>>>> index eb113e38f5e9..118f4bed32fd 100644
>>>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_doorbell_mgr.c
>>>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_doorbell_mgr.c
>>>> @@ -39,7 +39,7 @@ u32 amdgpu_mm_rdoorbell(struct amdgpu_device
>>>> *adev, u32 index)
>>>> return 0;
>>>> if (index < adev->doorbell.num_kernel_doorbells)
>>>> - return readl(adev->doorbell.ptr + index);
>>>> + return readl(adev->doorbell.cpu_addr + index);
>>>> DRM_ERROR("reading beyond doorbell aperture: 0x%08x!\n",
>>>> index);
>>>> return 0;
>>>> @@ -61,7 +61,7 @@ void amdgpu_mm_wdoorbell(struct amdgpu_device
>>>> *adev, u32 index, u32 v)
>>>> return;
>>>> if (index < adev->doorbell.num_kernel_doorbells)
>>>> - writel(v, adev->doorbell.ptr + index);
>>>> + writel(v, adev->doorbell.cpu_addr + index);
>>>> else
>>>> DRM_ERROR("writing beyond doorbell aperture: 0x%08x!\n",
>>>> index);
>>>> }
>>>> @@ -81,7 +81,7 @@ u64 amdgpu_mm_rdoorbell64(struct amdgpu_device
>>>> *adev, u32 index)
>>>> return 0;
>>>> if (index < adev->doorbell.num_kernel_doorbells)
>>>> - return atomic64_read((atomic64_t *)(adev->doorbell.ptr +
>>>> index));
>>>> + return atomic64_read((atomic64_t
>>>> *)(adev->doorbell.cpu_addr + index));
>>>> DRM_ERROR("reading beyond doorbell aperture: 0x%08x!\n",
>>>> index);
>>>> return 0;
>>>> @@ -103,11 +103,47 @@ void amdgpu_mm_wdoorbell64(struct
>>>> amdgpu_device *adev, u32 index, u64 v)
>>>> return;
>>>> if (index < adev->doorbell.num_kernel_doorbells)
>>>> - atomic64_set((atomic64_t *)(adev->doorbell.ptr + index), v);
>>>> + atomic64_set((atomic64_t *)(adev->doorbell.cpu_addr +
>>>> index), v);
>>>> else
>>>> DRM_ERROR("writing beyond doorbell aperture: 0x%08x!\n",
>>>> index);
>>>> }
>>>> +/**
>>>> + * amdgpu_doorbell_create_kernel_doorbells - Create kernel
>>>> doorbells for graphics
>>>> + *
>>>> + * @adev: amdgpu_device pointer
>>>> + *
>>>> + * Creates doorbells for graphics driver usages.
>>>> + * returns 0 on success, error otherwise.
>>>> + */
>>>> +int amdgpu_doorbell_create_kernel_doorbells(struct amdgpu_device
>>>> *adev)
>>>> +{
>>>> + int r;
>>>> + int size;
>>>> +
>>>> + /* Reserve first num_kernel_doorbells (page-aligned) for
>>>> kernel ops */
>>>> + size = ALIGN(adev->doorbell.num_kernel_doorbells *
>>>> sizeof(u32), PAGE_SIZE);
>>>> +
>>>> + /* Allocate an extra page for MES kernel usages (ring test) */
>>>> + adev->mes.db_start_dw_offset = size / sizeof(u32);
>>>> + size += PAGE_SIZE;
>>>
>>> This is initialized but not used, so I suspect it will temporary
>>> break the MES test? Or is the MES just implicitly using the correct
>>> offset somehow?
>>
>> I am not sure if I understand this comment properly, can you please
>> elaborate ?
>>
>> If you are talking about 'size', its just used below while creating
>> the doorbell BO.
>>
>> If you mean adev->mes.db_start_dw_offset, its being used in
>> amdgpu_mes_kernel_doorbell_get/free and amdgpu_mes_doorbell_init
>
> I was talking about adev->mes.db_start_dw_offset. But using this in
> amdgpu_mes_kernel_doorbell_get/free comes in a later patch, doesn't
> it? If yes, doesn't that break the MES test?
>
Ah, I get it now, and you are right, I though it would be better for
reviewer to see all KGD kernel level pages being created in the same
patch, but now I feel it would have been far better to do this in MES
kernel specific patch.
I will move this code in MES kernel doorbells page.
- Shashank
> Christian.
>
>>
>> So both of the variables are being used.
>>
>> - Shashank
>>
>>>
>>> Apart from that it looks good to me,
>>> Christian.
>>>
>>>> +
>>>> + r = amdgpu_bo_create_kernel(adev,
>>>> + size,
>>>> + PAGE_SIZE,
>>>> + AMDGPU_GEM_DOMAIN_DOORBELL,
>>>> + &adev->doorbell.kernel_doorbells,
>>>> + NULL,
>>>> + (void **)&adev->doorbell.cpu_addr);
>>>> + if (r) {
>>>> + DRM_ERROR("Failed to allocate kernel doorbells, err=%d\n",
>>>> r);
>>>> + return r;
>>>> + }
>>>> +
>>>> + adev->doorbell.num_kernel_doorbells = size / sizeof(u32);
>>>> + return 0;
>>>> +}
>>>> +
>>>> /*
>>>> * GPU doorbell aperture helpers function.
>>>> */
>>>> @@ -127,7 +163,6 @@ int amdgpu_doorbell_init(struct amdgpu_device
>>>> *adev)
>>>> adev->doorbell.base = 0;
>>>> adev->doorbell.size = 0;
>>>> adev->doorbell.num_kernel_doorbells = 0;
>>>> - adev->doorbell.ptr = NULL;
>>>> return 0;
>>>> }
>>>> @@ -156,12 +191,6 @@ int amdgpu_doorbell_init(struct
>>>> amdgpu_device *adev)
>>>> if (adev->asic_type >= CHIP_VEGA10)
>>>> adev->doorbell.num_kernel_doorbells += 0x400;
>>>> - adev->doorbell.ptr = ioremap(adev->doorbell.base,
>>>> - adev->doorbell.num_kernel_doorbells *
>>>> - sizeof(u32));
>>>> - if (adev->doorbell.ptr == NULL)
>>>> - return -ENOMEM;
>>>> -
>>>> return 0;
>>>> }
>>>> @@ -174,6 +203,7 @@ int amdgpu_doorbell_init(struct amdgpu_device
>>>> *adev)
>>>> */
>>>> void amdgpu_doorbell_fini(struct amdgpu_device *adev)
>>>> {
>>>> - iounmap(adev->doorbell.ptr);
>>>> - adev->doorbell.ptr = NULL;
>>>> + amdgpu_bo_free_kernel(&adev->doorbell.kernel_doorbells,
>>>> + NULL,
>>>> + (void **)&adev->doorbell.cpu_addr);
>>>> }
>>>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_mes.h
>>>> b/drivers/gpu/drm/amd/amdgpu/amdgpu_mes.h
>>>> index 547ec35691fa..a403418d5eac 100644
>>>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_mes.h
>>>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_mes.h
>>>> @@ -128,6 +128,9 @@ struct amdgpu_mes {
>>>> int (*kiq_hw_init)(struct
>>>> amdgpu_device *adev);
>>>> int (*kiq_hw_fini)(struct
>>>> amdgpu_device *adev);
>>>> + /* MES doorbells */
>>>> + uint32_t db_start_dw_offset;
>>>> +
>>>> /* ip specific functions */
>>>> const struct amdgpu_mes_funcs *funcs;
>>>> };
>>>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
>>>> b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
>>>> index 6d1587bbda52..c48e97646541 100644
>>>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
>>>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
>>>> @@ -1854,6 +1854,13 @@ int amdgpu_ttm_init(struct amdgpu_device *adev)
>>>> return r;
>>>> }
>>>> + /* Create a boorbell page for kernel usages */
>>>> + r = amdgpu_doorbell_create_kernel_doorbells(adev);
>>>> + if (r) {
>>>> + DRM_ERROR("Failed to initialize kernel doorbells.\n");
>>>> + return r;
>>>> + }
>>>> +
>>>> /* Initialize preemptible memory pool */
>>>> r = amdgpu_preempt_mgr_init(adev);
>>>> if (r) {
>>>
>
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